The last lines before I entered the gdb command 'bt':

Core was generated by `/usr/sbin/asterisk -f -vvvg -c'.
Program terminated with signal 6, Aborted.
#0  0xb7fa6410 in ?? ()

###########################################################
(gdb) bt
#0  0xb7fa6410 in ?? ()
#1  0xb67a19bc in ?? ()
#2  0x00000006 in ?? ()
#3  0x000009e5 in ?? ()
#4  0xb7e04811 in raise () from /lib/tls/i686/cmov/libc.so.6
#5  0xb7e05fb9 in abort () from /lib/tls/i686/cmov/libc.so.6
#6  0xb7e39dfa in __fsetlocking () from /lib/tls/i686/cmov/libc.so.6
#7  0xb7e4168f in mallopt () from /lib/tls/i686/cmov/libc.so.6
#8  0xb7e41732 in free () from /lib/tls/i686/cmov/libc.so.6
#9  0xb799a157 in _free_port_cfg () at misdn_config.c:463
#10 0xb799aec8 in misdn_cfg_init (this_max_ports=0) at misdn_config.c:1122
#11 0xb799b74e in misdn_cfg_reload () at misdn_config.c:1067
#12 0xb79903fb in reload_config () at chan_misdn.c:1045
#13 0xb799050c in misdn_reload (fd=12, argc=2, argv=0xb67a1e24)
    at chan_misdn.c:1059
#14 0x0808e0db in ast_cli_command (fd=12, s=0xb67a1f8c "misdn reload")
    at cli.c:1982
#15 0x0808e346 in ast_cli_command_multiple (fd=12, size=13,
    s=0xb67a21bc "misdn reload") at cli.c:2021
#16 0x0806f6d6 in netconsole (vconsole=0x8168ce0) at asterisk.c:941
#17 0x080f9f10 in dummy_start (data=0x81b9e60) at utils.c:852
#18 0xb7f8c240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#19 0xb7ea749e in clone () from /lib/tls/i686/cmov/libc.so.6


###########################################################
(gdb) bt full
#0  0xb7fa6410 in ?? ()
No symbol table info available.
#1  0xb67a19bc in ?? ()
No symbol table info available.
#2  0x00000006 in ?? ()
No symbol table info available.
#3  0x000009e5 in ?? ()
No symbol table info available.
#4  0xb7e04811 in raise () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
#5  0xb7e05fb9 in abort () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
#6  0xb7e39dfa in __fsetlocking () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
#7  0xb7e4168f in mallopt () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
#8  0xb7e41732 in free () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
#9  0xb799a157 in _free_port_cfg () at misdn_config.c:463
        i = 2
        j = <value optimized out>
        gn = <value optimized out>
#10 0xb799aec8 in misdn_cfg_init (this_max_ports=0) at misdn_config.c:1122
        config = "misdn.conf"
        cat = <value optimized out>
        p = <value optimized out>
        cfg = (struct ast_config *) 0x819caa0
        v = <value optimized out>
        __PRETTY_FUNCTION__ = "misdn_cfg_init"
#11 0xb799b74e in misdn_cfg_reload () at misdn_config.c:1067
No locals.
#12 0xb79903fb in reload_config () at chan_misdn.c:1045
        cfg_debug = <value optimized out>
        __PRETTY_FUNCTION__ = "reload_config"
#13 0xb799050c in misdn_reload (fd=12, argc=2, argv=0xb67a1e24)
    at chan_misdn.c:1059
No locals.
#14 0x0808e0db in ast_cli_command (fd=12, s=0xb67a1f8c "misdn reload")
    at cli.c:1982
        argv = {0x819c120 "misdn", 0x819c126 "reload", 0x0, 0x819c154 "",
  0x0 <repeats 60 times>}
        e = (struct ast_cli_entry *) 0xb79cd43c
        x = 2
        dup = 0x819c120 "misdn"
        tws = 0
#15 0x0808e346 in ast_cli_command_multiple (fd=12, size=13,
    s=0xb67a21bc "misdn reload") at cli.c:2021
        cmd = "misdn reload\000HESARRAY \"misdn\" \"misdn\"", '\0' <repeats 31 times>, "2446", '\0' <repeats 16 times>, "\230!z▒▒\217▒\000\000\000\000▒\221▒▒▒鷼#z▒G z▒\f\000\000\000\000\000Linux", '\0' <repeats 37 times>, "\024▒▒\000\000\000\000\000\000\000\000▒\217▒\000\000\000\000\000\000\000\000\r▒▒\214 z▒▒!z▒▒#z▒▒!z▒▒\217▒\214 z▒▒!z▒x!z▒\201\217▒\214 z▒\035\214\022\b▒!z▒▒!z▒\000\000\000\000,!z▒▒\001"...
        x = 13
        y = 2533
        count = 0
#16 0x0806f6d6 in netconsole (vconsole=0x8168ce0) at asterisk.c:941
        hostname = "flursserver", '\0' <repeats 52 times>
        tmp = "misdn reload\000\000/etc/asterisk/misdn.conf': \000Found\n\000 0\000logger mute silent", '\0' <repeats 270 times>, "\024\032▒", '\0' <repeats 56 times>, "\020\000\000\000Ȥ▒", '\0' <repeats 44 times>, "▒\017▒", '\0' <repeats 12 times>, "\200▒▒\000\000\000\000\f", '\0' <repeats 11 times>, "\021\000\000\000\000\000\000\000▒\217▒▒▒9q\001\000▒#z▒"
        res = <value optimized out>
        fds = {{fd = 12, events = 1, revents = 1}, {fd = 13, events = 1,
    revents = 0}}
        __PRETTY_FUNCTION__ = "netconsole"
#17 0x080f9f10 in dummy_start (data=0x81b9e60) at utils.c:852
        _buffer = {__routine = 0x8069fe0 <ast_unregister_thread>,
#18 0xb7f8c240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
No symbol table info available.
#19 0xb7ea749e in clone () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.


###########################################################
(gdb) thread apply all bt

Thread 10 (process 2446):
#0  0xb7fa6410 in ?? ()
#1  0xbfa66738 in ?? ()
#2  0x00000001 in ?? ()
#3  0xbfa6686b in ?? ()
#4  0xb7f9182b in __read_nocancel () from /lib/tls/i686/cmov/libpthread.so.0
#5  0x080fea0f in read_char (el=0x8174a98, cp=0xbfa6686b "") at read.c:296
#6  0x0810760f in el_gets (el=0x8174a98, nread=0xbfa66c04) at read.c:243
#7  0x0806e782 in main (argc=-1503077376, argv=0xa66c04bf) at asterisk.c:2982
#8  0xb7df0ea8 in __libc_start_main () from /lib/tls/i686/cmov/libc.so.6
#9  0x08057ab1 in ?? () at ../sysdeps/i386/elf/start.S:119

Thread 9 (process 2461):
#0  0xb7fa6410 in ?? ()
#1  0xb7dda338 in ?? ()
#2  0xffffffff in ?? ()
#3  0x00000001 in ?? ()
#4  0xb7e9d8f3 in poll () from /lib/tls/i686/cmov/libc.so.6
#5  0x0806f11e in listener (unused=0x0) at asterisk.c:980
#6  0x080f9f10 in dummy_start (data=0x8176b60) at utils.c:852
#7  0xb7f8c240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#8  0xb7ea749e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 8 (process 2471):
#0  0xb7fa6410 in ?? ()
#1  0xb7d9e418 in ?? ()
#2  0x00000009 in ?? ()
#3  0x00000000 in ?? ()

Thread 7 (process 2506):
#0  0xb7fa6410 in ?? ()
#1  0xb7d3d418 in ?? ()
#2  0x00000000 in ?? ()

Thread 6 (process 2507):
#0  0xb7fa6410 in ?? ()
#1  0xb7c6e318 in ?? ()
#2  0x000003e8 in ?? ()
#3  0x00000001 in ?? ()
#4  0xb7e9d8f3 in poll () from /lib/tls/i686/cmov/libc.so.6
#5  0x080a9be4 in ast_io_wait (ioc=0x81841a0, howlong=1000) at io.c:266
#6  0xb7cb18ba in do_monitor (data=0x0) at chan_sip.c:15579
#7  0x080f9f10 in dummy_start (data=0x81898f8) at utils.c:852
#8  0xb7f8c240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#9  0xb7ea749e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 5 (process 2513):
#0  0xb7fa6410 in ?? ()
#1  0xb7925458 in ?? ()
#2  0x00000000 in ?? ()

Thread 4 (process 2514):
#0  0xb7fa6410 in ?? ()
#1  0xb71243f8 in ?? ()
#2  0x00000000 in ?? ()

Thread 3 (process 2515):
#0  0xb7fa6410 in ?? ()
#1  0xb690f018 in ?? ()
#2  0xb7f08ff4 in ?? () from /lib/tls/i686/cmov/libc.so.6
#3  0xb690f004 in ?? ()
#4  0xb7e69ab6 in nanosleep () from /lib/tls/i686/cmov/libc.so.6
#5  0xb7e698db in sleep () from /lib/tls/i686/cmov/libc.so.6
#6  0xb6911e1f in scan_thread (unused=0x0) at pbx_spool.c:437
#7  0x080f9f10 in dummy_start (data=0x81ae288) at utils.c:852
#8  0xb7f8c240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#9  0xb7ea749e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 2 (process 2516):
#0  0xb7fa6410 in ?? ()
#1  0xb67de3e8 in ?? ()
#2  0xffffffff in ?? ()
#3  0x00000001 in ?? ()
#4  0xb7e9d8f3 in poll () from /lib/tls/i686/cmov/libc.so.6
#5  0x08068dd1 in monitor_sig_flags (unused=0x0) at asterisk.c:2524
#6  0x080f9f10 in dummy_start (data=0x81b9e10) at utils.c:852
#7  0xb7f8c240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#8  0xb7ea749e in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (process 2533):
#0  0xb7fa6410 in ?? ()
#1  0xb67a19bc in ?? ()
#2  0x00000006 in ?? ()
#3  0x000009e5 in ?? ()
#4  0xb7e04811 in raise () from /lib/tls/i686/cmov/libc.so.6
#5  0xb7e05fb9 in abort () from /lib/tls/i686/cmov/libc.so.6
#6  0xb7e39dfa in __fsetlocking () from /lib/tls/i686/cmov/libc.so.6
#7  0xb7e4168f in mallopt () from /lib/tls/i686/cmov/libc.so.6
#8  0xb7e41732 in free () from /lib/tls/i686/cmov/libc.so.6
#9  0xb799a157 in _free_port_cfg () at misdn_config.c:463
#10 0xb799aec8 in misdn_cfg_init (this_max_ports=0) at misdn_config.c:1122
#11 0xb799b74e in misdn_cfg_reload () at misdn_config.c:1067
#12 0xb79903fb in reload_config () at chan_misdn.c:1045
#13 0xb799050c in misdn_reload (fd=12, argc=2, argv=0xb67a1e24)
    at chan_misdn.c:1059
#14 0x0808e0db in ast_cli_command (fd=12, s=0xb67a1f8c "misdn reload")
    at cli.c:1982
#15 0x0808e346 in ast_cli_command_multiple (fd=12, size=13,
    s=0xb67a21bc "misdn reload") at cli.c:2021
#16 0x0806f6d6 in netconsole (vconsole=0x8168ce0) at asterisk.c:941
#17 0x080f9f10 in dummy_start (data=0x81b9e60) at utils.c:852
#18 0xb7f8c240 in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#19 0xb7ea749e in clone () from /lib/tls/i686/cmov/libc.so.6